Ensete Ventricosum) Suckers Under Different Horticultural Practices
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View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector South African Journal of Botany 2002, 68: 430–433 Copyright © NISC Pty Ltd Printed in South Africa — All rights reserved SOUTH AFRICAN JOURNAL OF BOTANY ISSN 0254–6299 Growth of enset (Ensete ventricosum) suckers under different horticultural practices M Diro1, 2, S Gebremariam2, A Zelleke2 and J van Staden*1 1 Research Centre for Plant Growth and Development, School of Botany and Zoology, University of Natal Pietermaritzburg, Private Bag X01, Scottsville 3209, South Africa 2 Ethiopian Agricultural Research Organisation, PO Box 2003, Addis Ababa, Ethiopia * Corresponding author, e-mail: [email protected] Received 11 March 2002, accepted in revised form 17 July 2002 The influence of three propagation practices and three fewer suckers. On the other hand, the halved corms, corm types of enset on the production of suckers was when uprooted and replanted immediately after removal investigated. After removal of apical buds, mother of apical buds or not uprooted from their original grow- corms were uprooted and immediately replanted, not ing sites, gave earlier differentiation of buds and pro- uprooted from original positions and uprooted and duced more suckers. The halved corms also gave more transferred to new planting holes three months later. medium to large suckers than whole and quartered Three corm types: whole, halved and quartered corms corms when evaluated across all the propagation meth- were used. Suckers were harvested one year after ods. An increase in the number of vigorous suckers removal of apical buds. After harvest, the suckers were from halved corms is possible because of elimination of sorted into three size groups: undersized, small and the strong apical dominance while leaving reasonable medium to large. The number of suckers produced per portions of the mother corm to sustain initiation, growth plot, from four planting holes, ranged from 40 to 141 and development of suckers. Therefore, halved corms depending on the treatments. Halved and quartered uprooted and immediately replanted or left in situ can mother corms, when transferred to new planting holes be used to produce more suckers with better growth. three months after removal of apical buds, produced Introduction Enset (Ensete ventricosum (Welw.) Cheesman) is a diploid source of food (Spring 1996). Enset is a productive crop, a (2n = 18) herbaceous perennial morphologically resembling source of income, a cultural medicine and feed for livestock. banana. The genera Ensete and Musa belong to the The plant is tolerant to transient drought once established. Musaceae. Enset is the vernacular name used in the Processed products can be stored for a long time without Amharic language in Ethiopia for E. ventricosum. Centres of spoiling thus ensuring stable food supply. Fibre, a by-prod- origin of Ensete are the lowland and mountain areas of uct when enset is processed, is used in local fibre factories Uganda, Tanzania and the Sudan (Smeds 1955) and and partially substitutes for fibre importation. At the environ- Ethiopia (Kuls cited by Westphal 1975). mental level, enset plantations reduce runoff, improve nutri- Horaninow (1862) was the first to describe the genus ent recycling and thus contribute to a sustainable agriculture. Ensete creating a single species, Ensete edule. Cheesman Wild species of Ensete propagate from seed. Cultivated (1947) revised the genus Ensete reporting 25 species. enset also produces seeds but only after a long juvenile peri- Baker and Simmonds (1953) identified the synonyms where- od. Seed germination is very low because of seed dorman- as Simmonds (1960) with further work reported only six cy. Moreover, since enset utilises its stored carbohydrate species, Ensete gilletii, E. homblei, E. perrieri and E. ventri- during fruiting and eventually dies, it is harvested before or cosum with an African distribution and E. glaucum and E. shortly after flowering, reducing viable seed production. superbum with an Asian distribution. Therefore, propagation by seed is not common. The plant is Enset (Ensete ventricosum) is widely distributed in Africa. usually multiplied vegetatively and grown as clones. Apical It adapted to altitudes between 1 500m and 3 000m in buds are removed from the whole or split corms, after Ethiopia (Bezuneh and Felleke 1966) and is mainly cultivat- uprooting or without uprooting the mother plant (Alemu and ed in the southern and southwestern parts of the country. Sandford 1991, Diro and Tabogie 1994), to initiate sucker- Here it plays a significant economic and social role. About 15 ing. During transplanting, enset growers sort the suckers million people in Ethiopia are dependent on enset as a into size groups. Undersized suckers are replanted in the South African Journal of Botany 2002, 68: 430–433 431 nursery and maintained for extended periods before being Research Centre. The mother plants were transplanted to ready for transplanting. Replanting the undersized suckers the experimental field a year before application of the treat- in the nursery lengthens the time to maturity and curtails pro- ments. Corms were cut so that they each had a 10cm to duction. Therefore, growers need more vigorous suckers of 15cm pseudostem. The cut surfaces of the corms were enset for cultivation. In banana cultivation, lateral shoots are exposed to sunlight for 48h before covering them with soil. referred to collectively as suckers and those that bear nar- After emergence, plants were regularly weeded. row sword leaves and are attached to the mother rhizome are called sword suckers, which are preferred for planting Data collection since they produce fruit more quickly than smaller ones or pieces of corm (Simmonds 1966, Stover and Simmonds Data collection commenced three months after removal of 1987). Moreover, small and weak suckers are less produc- the apical buds (RAB) and continued during the course of tive (Perez 1991). The use of vigorous suckers is important growth at monthly intervals until the 12th month. Final data to ensure success in establishment and subsequent per- collection was performed after suckers were harvested a formance of enset leading to early and higher yields. Gowen year after removal of the apical buds. The final data were (1995) reported that it is possible to produce more suckers used to evaluate the effects of treatments on sucker produc- of plantains by altering the techniques of traditional propa- tion. Suckers were categorised in three size groups: namely gation. Belhu et al. (1994) reported that more enset suckers undersized, small and medium to large. Categorisation of could be produced from halved corms. Usually, however, the suckers was based on the cultivation practices of farm- suckers are not evaluated in terms of their size and infor- ers around the Centre. Undersized suckers are those that mation is lacking on the effect of corm type under different are replanted in a nursery for onward growth in a group of methods of propagation. Therefore, vegetative enset propa- about three or left attached to the mother corm. Small suck- gation was investigated. This paper reports the growth of ers are those that can be planted directly into the field when- suckers, in number over time, and the influence of method ever there is a shortage of bigger ones. Usually they need of propagation and corm type on sucker production. further growth before placing them in field plantations. Medium to large suckers are those that can be planted Materials and Methods directly into the field. For the measurements of vegetative growth of suckers, Study area pseudostem diameter and sucker heights were recorded for 20 suckers every month. For the final measurements 10 The study was conducted at Areka Agricultural Research suckers per plot from each size group were randomly sam- Centre, southern Ethiopia. The Centre is situated at latitude pled. The data collected were subjected to statistical analy- 7°04’N, longitude 37°41’E and at an altitude of 1 800m with sis using the MSTATC, computer software developed in 1 564mm (eight year average) mean annual rainfall and 1991 by Michigan State University. Duncan’s Multiple Range 64% (three year average) relative humidity. The soil at the Test (DMRT) at a 5% probability level was used to separate site is a silt loam with a pH of 4.5 to 4.9 in the top 30cm of significant means. soil. Results and Discussion Treatments and experimental design Growth of suckers The experiment was designed to examine the effects of three vegetative propagation methods and three corm types More suckers emerged from halved corms three months on sucker growth. The three propagation methods were: after removal of apical buds when mother corms were parent corm uprooted, apical bud removed and corm uprooted and replanted immediately or not uprooted from replanted the same day of uprooting (M1); pseudostem of their original positions (Figure 1). The number of suckers in parent corm cut at soil level, apical bud removed, the corm these treatments reached a maximum five months after covered with soil and left at the same place for a year (M2); removal of apical buds, two months earlier than many of the and pseudostem of the parent corm cut at soil level, apical treatment combinations. Relatively fewer suckers emerged bud removed, the corm covered with soil and transferred to at this time from the whole corms under all propagation a new planting hole after three months (M3). The three corm methods. This increased slowly for seven months after types were the whole corm (C1); halved corms (C2); and removal of apical buds. Many of the late emerged suckers quartered corms (C3). The experiment was laid out as a from the whole corms survived until final harvest of suckers. randomised complete block design with four replications. This appeared to be due to less competition and larger The factorial combinations of three propagation methods reserves in the whole corms.